By Sarah Kaplan
All along the western Canadian coast, mussels are dying. Their blobby bodies are swollen by tumors. The blood-like fluid that fills their interiors is clogged with malignant cells. They’re all sick with the same thing: cancer. And it seems to be spreading.
For all its harrowing, terrifying damage, the saving grace of cancer has always been that it dies with its host. Its destructive power comes from turning victims’ own cells against them and making them run amok.
But when molecular biologist Stephen Goff biopsied these mussels, he found something strange. The tumor cells didn’t have the same DNA as their host. Instead, every mussel was being killed by the same line of cancerous cells, which were jumping from one individual to the next like a virus. The mussels, as well as two other species of bivalve examined by Goff and his colleagues, are dying from contagious cancer.
Goff’s study, which was published Wednesday in the journal Nature, doubles the number of species known to suffer from transmissible cancers. And in one case, clams were being killed by cancer cells that come from an entirely different species.
The results, Goff said, suggest that this communicable form of the disease isn’t as rare as scientists once thought. Read more …